updating koji builder sop

Signed-off-by: Pedro Moura <pmoura@redhat.com>

modules/sysadmin_guide/pages/koji-builder-setup.adoc

@@ -2,6 +2,38 @@
 
 == Contents
 
+* <<_upgrade_builders>>
+** <<_staging_environment>>
+** <<_production_environment>>
+
+== Upgrades Builders
+
+It is recommended to upgrade or reinstall all builders after each release. To do it, usually the builders are upgraded and virtual machines reinstalled. First they should be upgraded in staging environment to make sure everything is working properly before starting on production.
+
+=== Staging Environment
+
+Follow the process to upgrade builders in staging environment:
+
+. Update the virt-install path on the builders in ansible repository, like in this https://pagure.io/fedora-infra/ansible/c/af94db8ab88588aa8dc2c20893b2487afb7f7777?branch=main[example]
+. Each builder virtual machine is removed, either via virt-inst-dest or manually, and the buildvm.yml playbook is run to deploy them. 
+. The hub is re-installed or upgraded with 'dnf --refresh --releasever <release> distro-sync'.
+. Test builds are done to make sure everything is working.
+
+=== Production Environment
+
+For production a similar process is followed, but to avoid outages, builders are disabled, reinstalled and re-added small groups at a time.
+
+
+////
+From this comment below, everything is going to be deleted
+Keeping all commented for reference while writing a new SOP
+////
+
+////
+= Setup Koji Builder SOP
+
+== Contents
+
 * <<_builder_setup>>
 ** <<_network_overview>>
 ** <<_setup_overview>>
@@ -117,3 +149,4 @@ virsh autostart $builder_fqdn
 ** disable selinux in `/etc/sysconfig/selinux`
 ** `reboot`
 ** ask a koji admin to re-enable the host
+////